Liquid crystal displays (LCDs) continue to improve in cost and performance, becoming a preferred display type for many computer, instrumentation, and entertainment applications. Typical LCD-based mobile phones, notebooks, and monitors include a light guide plate (LGP) for receiving light from a light source and redistributing the light uniformly across the light output surface of the LGP. The light source, conventionally being a long, linear cold-cathode fluorescent lamp, has evolved to a plurality of discrete light sources such as light emitting diodes (LEDs). In order to achieve increased luminance uniformity in an LED backlight, the luminance variation near the corners and sides of the light guide plate needs to be addressed.
Some LGPs have been proposed to suppress luminance variation near the corners by increasing density of the light reflection or extraction features near the corners, but few if any, also suppress the luminance variation near the sides of the LGPs. Those LGPs suppressing luminance variation near the corners typically have two or more sets of dots of different sizes, such as disclosed in U.S. Pat. No. 7,478,942 (Kim et al).
While the prior art LGPs are capable of suppressing luminance variation near the corners to a certain degree, they are still not satisfactory due to the complexity in the manufacture of those LGPs. Thus, there remains a need for an LGP that can be easily manufactured and is capable of suppressing luminance variation near the corners and sides of the LGP.